Air pump with electric motor

ABSTRACT

An electric pumping device includes motor powered by batteries and a eccentric crank is driven by the motor so as to operate a piston assembly. The piston assembly generates pressurized air into the object such as a tire via an outlet. A pressure gauge assembly is connected to a side of the body of the pumping device and includes a gauge member having marks which can be seen via a window so that the user can control precisely the pressure that the pumping device generated.

FIELD OF THE INVENTION

[0001] The present invention relates to a portable electric pumping device powered by batteries and can be easily pump the tires of bicycles.

BACKGROUND OF THE INVENTION

[0002] A conventional bicycle pump 1 is shown in FIG. 1 and generally includes a tubular body with a piston movably received therein and a handle is connected to the piston rod which extends from a first end of the body. A valve head is connected to the other end of the body so that the user may hold the body and operating the handle to inflate the tires of bicycles by reciprocally operating the handle. The pump 1 is operated manually and takes a lot of time and efforts. Besides, the result of the pressure in the tire cannot be controlled precisely.

[0003] The present invention intends to provide a portable electric pumping device that employs a motor driving a crank which is connected to a piston system so as to inflate the tires of bicycles conveniently.

SUMMARY OF THE INVENTION

[0004] The primary object of the present invention is to provide a portable electric pumping device for inflating tires or other inflatable parts of bicycles. The pumping device is easy to use and the pressure output can be controlled by checking the gauge member via a window of the device.

[0005] The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006]FIG. 1 is a perspective view to show a conventional pumping device;

[0007]FIG. 2 is an exploded view to show the electric pumping device of the present invention;

[0008]FIG. 3 is a cross sectional view to show the electric pumping device of the present invention;

[0009]FIG. 4 is a cross sectional view to show the electric pumping device of the present invention, wherein the piston assembly is operated;

[0010]FIG. 5 is a cross sectional view to show the electric pumping device of the present invention, wherein the piston assembly reaches its far-most position, and

[0011]FIG. 6 is a cross sectional view to show the electric pumping device of the present invention, wherein the piston assembly is retracted.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0012] Referring to FIGS. 2 and 3, the electric pumping device 5 of the present invention comprises a head 10 having an outlet 11 defined in an end of the head 10 and a cam member 17 connected to the other end of the head 10 so as to force the inlet 11 to be engaged with a valve of a tire (not shown).

[0013] A passage 13 is defined in the head 10 and in communicating between the outlet 11 and a chamber 12. A block 14 is located in the passage 13 and an end of a spring 16 is connected to the sealing block 14. A cylinder 561 is received in the head 10 and a hole 564 is defined through a close end of the cylinder 561. The passage 13 communicates with the hole 564 and a sealing pad 161 is connected to the other end of the spring 16 so as to movably seal the hole 564. A side path 15 communicates with the passage 13 and the outlet 11.

[0014] A receiving area 20 is defined in a side of the head 10 and a communication hole 23 is in communication between the outlet 11 and the receiving area 20. The receiving area 20 has an inner threaded section 21 and a window 22 is defined through a wall of the receiving area 20.

[0015] A pressure gauge assembly 24 is received in the receiving area 20 and includes a sealing member 25, a gauge member 26, a spring 27 having one end received in the gauge member 26, a fixing member 28 and an end cap 29. The sealing member 25 is engaged the communication hole 23 and the other end of the spring 27 is mounted to a protrusion 282 on the fixing member 28. The fixing member 28 has an outer threaded section 281 which is engaged with the inner threaded section 21 of the receiving area 20. The end cap 29 has a threaded section 291 which is engaged with the inner threaded section 21 of the receiving area 20. The gauge member 26 of the pressure gauge assembly 24 has scale marks which are located corresponding to the window 22 so that the user knows the pressure by checks the marks via the window 22.

[0016] A body 30 is connected to the head 10 and has a battery box 31 received therein so that batteries 32 are received in the battery box 31. An inflating assembly 50 is received in the chamber 12 of the head 10 and includes a motor 51 which has one end connected to the battery box 31 by a switch 531, the control unit 53 and a signal part 54, the other end of the motor 51 has a shaft 52 which is connected to a small bevel gear 551 which is engaged with a large bevel gear 552. A driving crank 553 is eccentrically connected to the large bevel gear 552 so that when operating the switch 531, the driving crank 533 is rotated and at a desired speed.

[0017] A piston assembly 56 is connected to the driving crank 553 and reciprocally received in the cylinder 561. A one-direction valve 562 is connected to the piston assembly 56 so that the one-direction valve 562 pushes air in the pressure chamber 561 irreversibly toward the passage 13. A path 560 is defined through the piston assembly 56 and sealed by the one-direction valve 562. The one-direction valve 562 has one end connected to the piston assembly 56 and the other end of the one-direction valve 562 covers onto the piston assembly 56 so as to seal the path 560. A sealing ring 563 is mounted to the piston assembly 56 such that the piston assembly 56 snugly moved in the inner periphery of the cylinder 561.

[0018] Referring to FIGS. 4 to 6, when the motor 51 is activated, the driving crank 553 makes the piston assembly 56 reciprocally move in the cylinder 561. The air in the cylinder 561 is pushed through the hole 564 and the pad 161 is pushed away from the hole 564. The pressurized air enters the side path 15 and outputs from the outlet 11. The pressure, in the meanwhile, pushes the sealing member 25 which compresses the spring 27 so that the gauge member 26 is moved corresponding to the pressure. The user knows the pressure in the tire by checking the scale marks on the gauge member 26.

[0019] When the piston assembly 56 is retracted, air comes into the cylinder 561 via the path 560 and the one-direction valve 562 is pushed to let the air enter the interior of the cylinder 561. In the meanwhile, the pad 161 is pushed by the spring 16 and seals the hole 564 again.

[0020] While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention. 

What is claimed is:
 1. An electric pumping device comprising: a head having an outlet defined in an end of the head and a passage defined in the head, the passage being in communicating between the outlet and a chamber, a block located in the passage and an end of a spring connected to the sealing block, a cylinder received in the head and a hole defined through a close end of the cylinder, the passage communicating with the hole, a sealing pad connected to the other end of the spring and movably sealing the hole, a side path communicating with the passage and the outlet, a receiving area defined in a side of the head and a communication hole in communication between the outlet and the receiving area, a pressure gauge assembly received in the receiving area, a cam member connected to the other end of the head; a body having a battery box received therein and an inflating assembly received in the chamber of the head, the inflating assembly including a motor which has one end connected to the battery box by a switch and the control unit, the other end of the motor has a shaft which is connected to a small bevel gear which is engaged with a large bevel gear, a driving crank eccentrically connected to the large bevel gear, and a piston assembly connected to the driving crank and reciprocally received in the cylinder, a one-direction valve connected to the piston assembly so that the one-direction valve pushes air in the pressure chamber irreversibly toward the passage, a path defined through the piston assembly and being sealed by the one-direction valve.
 2. The device as claimed in claim 1, wherein the one-direction valve has one end connected to the piston assembly and the other end of the one-direction valve covers onto the piston assembly.
 3. The device as claimed in claim 1, wherein a sealing ring is mounted to the piston assembly.
 4. The device as claimed in claim 1, wherein the receiving area has a inner threaded section and a window is defined through a wall of the receiving area, the pressure gauge assembly having scale marks which are located corresponding to the window.
 5. The device as claimed in claim 4, wherein the pressure gauge assembly includes a sealing member, a gauge member, a spring having one end received in the gauge member, a fixing member and an end cap, the sealing member engaged the communication hole and the other end of the spring mounted to a protrusion on the fixing member, the fixing member having an outer threaded section which is engaged with the inner threaded section of the receiving area, the end cap having a threaded section which is engaged with the inner threaded section of the receiving area. 